Dyeing polyamide fibers with pelargonic acid



United States Patent DYEING POLYAMIDE FIBERS WITH PELARGONIC ACID Ronald R. Luongo, Wilmington, Del., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware No Drawing. Filed Nov. 23, 1966, Ser. No. 596,470

Int. Cl. D06p /04 U.S. Cl. 8173 3 Claims ABSTRACT OF THE DISCLOSURE The process of dyeing synthetic fibers, said fibers consisting essentially of the polymeric reaction product of bis(para-aminocyclohexyl)methane and a diacid selected from the group consisting of dodecanedioic acid and nonanedioic acid, comprising the steps of:

This invention relates to the dyeing of polyamide fibers and more particularly to an improved dye assistant composition and the improved process for using it to aid the dyeing of fibers made from aliphatic dicarboxylic acid polymerized with bis(para-aminocyclohexyl)methane.

Dyeing is a difiicult problem due to the hydrophobic nature of fibers spun from a polymer of bis (para-aminocyclohexyl)methane and an aliphatic dicarboxylic acid. More specifically, obtaining satisfactory dyeing, particularly in depth of shade and light fastness, is difiicult with this type of fiber because they are inherently stain and soil resistant. Two methods which are known to increase color penetration into fibers which otherwise dye with diificulty, for example, polyester fibers, are pressure dyeing at elevated temperatures and using a dye carrier at temperatures near dye bath boil.

Several carriers are available which aid in dyeing polyester fibers and which provide a partial solution to the dyeing of polyamide fibers spun from PACM-12 and PACM9. Some carriers which have been previously utilized are butylbenzoates, orthophenylphenol, salicylic esters and acids, benzoic esters and acids, chlorinated benzene and aliphatic alcohols. Use of these carriers, however presents practical deficiencies in one or more of the desirable carrier characteristics, for instance, toxicity, odor, and ease of removal after dyeing process is finished.

The following definitions will suffice for the terms and abbreviations as used in the foregoing and subsequent specification and claims: carriera chemical assistant having limited water solubility but which aids in absorption and penetration of a dye into a fiber or fabric; dyeas herein used includes dye of the disperse, direct, acid, basic and premetallized types; disperse dyeas herein used can include azo, nitroarylamine and anthroquinone compounds; dye bath-an aqueous dispersion of a dye into which a fiber is submersed for dyeing, which may also contain a carrier and a dispersing agent; dye exhaustthe term applied to the amount of dye exhausted or depleted from the dye bath during a dye cycle, usually measured in percent; fiberas used herein will include filaments, fibers, bristles, films, flakes, fabrics, and related products formed from the described polyamides; PACM-12-the abbreviation for the polyamide reaction product of dodecanedioic acid and ice bis(para-aminocyclo hexyl)methane; PACM9the abbreviation for the polyamide reaction product of nonanedioic acid and his (paraaminocyclohexyl)methane.

In accordance with the present invention there is provided a novel dye composition useful for dyeing polyamide fibers, particularly fibers spun from PACM-9 and PACM-12. The dye composition is an aqueous dispersion containing at least about 1% of a monocarboxylic acid having '9 carbon atoms and a dye. Preferably the dispersion contains from about 1% to about 30% of the acid. The percentages expressed are by weight and based on the amount of fiber to be dyed. Generally, any aliphatic monocarboxylic acid having 9 carbon atoms may be used, but pelargonic acid is preferable.

The pelargonic acid dye carrier is generally predispersed by the addition of a dispersing agent with agitation. The use of a dispersing agent is not a necessity, but facilitates obtaining a stable dispersion. Generally, good dye exhaust is achieved when the pelargonic acid is employed in concentrations of about 1% to 30% by weight based on the weight of fiber to be dyed. Best results are obtained when a preferable concentration of from 10% to 30% of pelargonic acid is utilized. The exact amount of pelargonic acid to be used depends upon the depth of shade desired. Lighter shades are achieved by using amounts of acid in lower concentrations and heavier shades, i.c., greater dye penetration, by using amounts toward the upper limits of the above concentration ranges. Additionally, the pelargonic acid may be formed from its sodium salt, sodium pelargonate.

The dispersing agents employed are generally surface active agents of the anionic or nonionic type and are generally mixed with pelargonic acid to the extent of about 2% to 30% by weight, based on the weight of pelargonic acid being dispersed. To achieve a desired dispersion, a preferable concentration of dispersing agent of from 5% to 15% by weight, based on the weight of pelargonic acid to be dispersed, is utilized. In the dyeing of fibers with acid dyes, it is preferred to use an anionic dispersing agent to disperse the pelargonic acid in order to improve the levelness of dyeing. For disperse dyes, either anionic or nonionic dispersing agents can be used. A typical pelargonic acid dispersion for use with disperse dyes contains parts by weight of pelargonic acid, 12 parts by weight of water and 2 parts by weight of a condensation product of C fatty alcohol with 20 moles of ethylene oxide and 6 parts lauryl sulfate salt of diethylcyclohexylamine. Another pelargonic acid dispersion for use with disperse dyes contains 30 parts by weight of pelargonic acid, 3 parts by weight of polyvinyl alcohol, 67 parts of water, and 0.03 part of sodium lauryl sulfate. A typical pelargonic acid dispersion for use with acid dyes contains 15 parts by weight pelargonic acid, 3.75 parts by weight of sodium hydroxide, 1 part by weight of a condensation product of C fatty alcohol with 20 moles of ethylene oxide, 1 part by weight of a 60% active ingredient solution of condensation products of tallow amine with 50 moles of ethylene oxide, and sufficient water to dilute the mixture to a total of 200 parts by weight. A second dispersion for use with acid dyes contains 7.5 parts of pelargonic acid, 2.2 parts of caustic soda, 71.8 parts of water and 0.5 part of a con densation product of C fatty alcohol with 20 moles ethylene oxide.

A process for dyeing synthetic PACM fibers comprises predispersing a mixture of 80% pelargonic acid, 8% dispersing agent and 12% water. Fibers to be dyed are pre scoured in a convention-a1 manner to remove waxes, oils and the like. A dye bath is prepared by using an amount of the above predispersion to provide from 1% to 20% of pelargonic acid based on the weight of fiber to be dyed. An additional 2% of a dispersing agent based on the weight of fiber to be dyed is then added to obtain a more thorough dispersion. The fiber is then introduced into the bath which is at room temperature and allowed to thoroughly wet out. Thi may require from 10 to 15 minutes. At this point for dispersed dyes, or if sodium pelargonate has been used, the pH of the bath is adjusted to within a range from about 3.5 to about 4.5. Then bath is then heated slowly, at a rate of about 10 F., (6 C.) per 10 minutes, to a temperature of about 120 F. (49 C.), at which point the dye is added. The bath is then slowly raised to a temperature of about 200 F. (93 C.). The bath is held at that temperature for a length of time depending upon the degree of levelness achieved and depth of shade desired, usually about one hour. At the end of this time, the fiber is scoured in a fresh bath which can contain alkali and about 2% of a dispersing agent, based on the weight of fiber being scoured, to help remove the pelargonic acid and excess dye. The fiber is then rinsed and dried.

The following examples are illustrative of the invention. All percentages and parts therein are by weight, based on the amount of fiber being dyed, unless otherwise indicated.

EXAMPLE I Four aqueous predispersions are first prepared by vigorous agitation of the components. Predispersion One contains 0.5 part by weight of pelargonic acid, 0.0125 part by weight of a condensation product of C fatty alcohol with 20 moles ethylene oxide, and 0.0375 part by weight lauryl sulfate salt of diethylcyclohexylamine, combined with 50 parts by weightof water with vigorous agitation. Predispersion Two contains 0.05 part of the sodium salt of No. 50 White Oil sulfonate in parts water. Predispersion Three contains 0.05 part of 60% active ingredient solution of condensation products of tallow amine with 50 moles ethylene oxide in 5 parts water. Predispersion Four contains 0.1 part of CI. dispersed Blue 60, predominantly 1,4-diamino-anthraquinone-N-gamma methoxy-propyl-2,3-dicarboximide, in 40 parts water. The four predispersions are added sequentially to 100 parts water with vigorous agitation. The thus prepared dye bath is heated to 80 F. (23 C.). 5 parts PACM-l2 fiber is introduced into the bath and worked for 15 minutes. The bath is heated stepwise raising the temperature F. (6 C.) every 10 minutes until the bath temperature reaches 200 F. (93 C.). After holding the temperature at 200 F. (93 C.) for 60 minutes, the fiber is removed from the dye bath, scoured in an alkaline bath at 180 F. (82 C.) for 30 minutes, and dried. The alkaline scouring bath is prepared by incorporating with vigorous agitation into 200 parts water, 0.15 part soda ash and 0.05 part of a 60% as is solution of condensation products of tallow amine with 50 moles ethylene oxide.

The fiber is dyed throughout to a uniform blue shade. The dye exhaustion from the dye bath is 65%, measured by means of a differential photometer.

EXAMPLE II To 100 parts water, 0.05 part of 60% active ingredient solution of condensation products of tallow amine with 50 moles ethylene oxide, and 0.05 part of the sodium salt of No. 50 White Oil sulfonate are added 0.5 part pelargonic acid and 0.2 part caustic soda followed by 0.05 part of a condensation product of C fatty alcohol with 20 moles ethylene oxide. The pH is adjusted to 4.5 by addition of 10% sulfuric acid. Then 0.1 part of Cl. dispersed Blue 60 is added. The weight is then adjusted to a total of 200 parts by addition of water. Prescoured 5 parts PACM-9 fiber is introduced into the bath which is 80 F. (23 C.). The temperature is then raised to 200 F. (93 C.) by heating at a rate of 10 F. per 10 minutes (5.5 C./10 mins.) and held at that temperature for one hour.

EXAMPLE III To 100 parts water add 1.5 parts pelargonic acid and 0.42 part caustic soda followed by 0.15 part of a condensation product of C fatty alcohol with 20 moles ethylene oxide and 0.53 part monosodium phosphate. The pH is adjusted to within a range of 3.5 to 4.0 by the addition of phosphoric acid. Then 0.1 part of Cl. No. 62055 dye is added. The dye bath is adjusted to 200 parts of water. Prescoured 5 parts PACM-12 fiber is introduced into the bath which is set at F. (20 C.). The temperature is then raised to 200 F. C.) by heating at a rate of 10 F. per 10 minutes (5.5 C. per 10 minutes) and held at Wthat temperature for 1 /2 hours. The dye exhaust is 94 o.

EXAMPLES IV-IX Additional examples are prepared as in Examples I and II except that the concentration of pelargonic acid in the dye bath is d creased according to the amount indicated in the following Table I. The degree of dye exhuastion from the bath is measured in each case by means of a differential photometer.

TABLE I Percent dye exhaust 011- Exarnple N0. Percent carrier PAOM-12 PACM-9 EXAMPLES X-XV The procedure of Example I is followed to dye samples of PACM-12 using other carriers selected from the monocarboxylic aliphatic acid series. In each Example 15% acid is used based on the weight of fiber being dyed. The results are listed in Table II:

TABLE II No. of carbon atoms in straight Percent dye Example No. chain exhaust EXAMPLES XVI-XIX Following procedure of Example IV, PACM-l2 fibers are dyed using other dyes in place of C.I. dispersed Blue 60 to show the usefulness as a carrier for several classes of dyes. Pelargonic acid carrier is persent in an amount of 15 by weight. The percent of dye exhaustion for the substituted dyes is given in Table III.

The carrier of the subject invention provides readily dispersible formulations which permit highly efficient and economical carrier compositions which may be employed with dispersed dyes, acid dyes, basic dyes, direct dyes, or premetallized dyes. The presence of this carrier in the dye bath insures thorough penetration of the dye into the fiber which is necessary for adequate wash fastness and light fastness and the attainment of deep shades in practical dyeing times.

Although specific embodiments of the subject invention have been described exemplified in the foregoing portion of the specification, it is manifest that diverse equivalent modifications may be elfected without deviating from the spirit of the invention or the scope of the annexed claims.

6 maintaining the temperature of the bath at about 90 C. for about 1 hour, and scouring said fibers in an alkaline bath. 2. The process of claim 1 wherein said pelargonic TABLE III Percent ye Example No. Dye Dye class exhaust XVI Acid dyes:

Colour Index No. 62055 Anthraquinone. 92 4-ehloro-2-trifiuoromethylaniline Azo 90 2-amino-1-napl1thol-3-sulfonic acid Na salt.

Colour Index No. 18950 Pyrazolone 90 XVII Direct dyes: Colour Index N 0. 22310.... Benzidine 60 XVIII Premetallized dyes:

Colour Inedx N 0. 12715 2:1 metal complex. 94 Colour Index No. 15711 1:1 metal complex- 60 XIX Disperse dyes:

Colour Index No. 61505 Anthraquinone- 77 l-amino-4-hydroxy-2-phenoxy 2111- .....do 90 thraquinone (Dispersed Red 602).

Colour Index No. 11110 Azo 96 C.I. dispersed Blue 60 predominantly Anthraquinone. 73

1,4-diaminoanthraquinone-N-gamma-methoxy-propyl-2,3-d1carboximide.

acid is in the form of an alkali metal salt.

3. The process of claim 1 wherein said dye is selected from the group consisting of disperse dyes, acid dyes, basic dyes, direct dyes, and premetallized dyes.

References Cited FOREIGN PATENTS 981,467 1/1965 Great Britain.

GEORGE F. LESMES, Primary Examiner T. J. HERBERT, 112., Assistant Examiner U.S. Cl. X.R. 8-92, 174 

